Conventional force sensors include those which place a quantum tunneling composite (QTC) in a load path of a force to be under strain from the force. The electrical resistance of the quantum tunneling composite changes with changes in the force. The conventional QTC force sensors determine the force from a measurement of the electrical resistance. The conventional QTC force sensor is suited to measuring a “point force” at a “point location” on the QTC material because the electrical resistance of the QTC material undergoes a change from applying a point force to a point location on the QTC material but additional loads will reduce the overall resistance of the QTC material (i.e., the QTC material acts like a plurality of resistors connected in parallel). QTC force sensors and quantum tunneling composites (i.e., QTC materials) are available from Peratech Ltd whose www website is peratech.co.uk. Known QTC materials include those whose electrical resistance is temperature dependent.
Conventional strain gages include those which rely on a change in electrical resistance of a resistor placed under strain. Other conventional methods to measure strain using SAW (surface acoustic wave) technology or magnetostrictive materials are known.
What is needed is an improved force sensor and an improved strain sensor and methods for measuring same.